Fix performance regression in WebGL to 2D canvas draws.

third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 631 matching lines @@
     shouldFailContextCreationForTesting = true;
 }
 
 ImageBitmap* WebGLRenderingContextBase::transferToImageBitmapBase()
 {
     if (!drawingBuffer())
         return nullptr;
     return ImageBitmap::create(drawingBuffer()->transferToStaticBitmapImage());
 }
 
-PassRefPtr<Image> WebGLRenderingContextBase::getImage(SnapshotReason reason) const
+PassRefPtr<Image> WebGLRenderingContextBase::getImage(AccelerationHint hint, SnapshotReason reason) const
 {
     if (!drawingBuffer())
         return nullptr;
 
     drawingBuffer()->commit();
     IntSize size = clampedCanvasSize();
     OpacityMode opacityMode = creationAttributes().hasAlpha() ? NonOpaque : Opaque;
     std::unique_ptr<AcceleratedImageBufferSurface> surface = wrapUnique(new AcceleratedImageBufferSurface(size, opacityMode));
     if (!surface->isValid())
         return nullptr;
     std::unique_ptr<ImageBuffer> buffer = ImageBuffer::create(std::move(surface));
     if (!buffer->copyRenderingResultsFromDrawingBuffer(drawingBuffer(), BackBuffer)) {
         // copyRenderingResultsFromDrawingBuffer is expected to always succeed because we've
         // explicitly created an Accelerated surface and have already validated it.
         NOTREACHED();
         return nullptr;
     }
-    return buffer->newImageSnapshot(PreferAcceleration, reason);
+    return buffer->newImageSnapshot(hint, reason);
 }
 
 namespace {
 
 // ES2 enums
 static const GLenum kSupportedInternalFormatsES2[] = {
     GL_RGB,
     GL_RGBA,
     GL_LUMINANCE_ALPHA,
     GL_LUMINANCE,
@@ skipping 5756 matching lines @@
 
 void WebGLRenderingContextBase::getHTMLOrOffscreenCanvas(HTMLCanvasElementOrOffscreenCanvas& result) const
 {
     if (canvas())
         result.setHTMLCanvasElement(canvas());
     else
         result.setOffscreenCanvas(getOffscreenCanvas());
 }
 
 } // namespace blink